用matlab求二重积分[1+cos(6*pi*x+8*pi*y)]*exp(-j*2*pi*(3*x+4*y)),试了好多次貌似都有错syms x y>> double (int(int(1+cos(6*pi*x+8*pi*y)*exp(-j*2*pi*(3*x+4*y)),-inf,inf),-inf,inf))Warning:Could not attach the property of being closeto the

Question

用matlab求二重积分[1+cos(6*pi*x+8*pi*y)]*exp(-j*2*pi*(3*x+4*y)),试了好多次貌似都有错
syms x y
>> double (int(int(1+cos(6*pi*x+8*pi*y)*exp(-j*2*pi*(3*x+4*y)),-inf,inf),-inf,inf))
Warning:Could not attach the property of being close
to the limit point to limit variable [limit]
Warning:Explicit integral could not be found.
Error using ==> mupadmex
Error in MuPAD command:DOUBLE cannot convert the
input expression into a double array.

Answer 1

function f=fun(x,y)
f=1+cos(6*pi.*x+8*pi.*y).*exp(-j*2*pi*(3.*x+4.*y));
end
>> f=@(x,y) fun(x,y);
Q=dblquad(f,0,2*pi,0,2*pi)
Q =
59.2170 - 0.0001i
>> f=@(x,y)fun(x,y);
Q=dblquad(f,-inf,inf,-inf,inf)
Q =
NaN + NaNi